Torricelli barometer or "mercury column barometer." The atmospheric pressure is balanced by a column of mercury surmounted by a closed and empty space. A process invented by Evangelista Torricelli (1643 -1647) Florence - Italy. In perfect condition, the indications are perfectly legible, the walnut support for the column is 92 cm x 10 cm x 4 cm, weight 1.372 kg See photos Packaging material is included in the shipping costs.